Why This Job is Featured on The SaaS Jobs
Platform engineering roles sit at the center of mature SaaS organizations, where multiple product teams depend on shared services to ship reliably. This Staff Software Engineer, Core Platforms position focuses on the internal systems and APIs that underpin customer-facing experiences, spanning domains like payments, reporting, access, workflows, and compliance. The scope signals a SaaS environment with established product lines and meaningful scale, where platform decisions directly influence velocity, reliability, and operational risk.
For a long-term SaaS career, this kind of work builds durable leverage. Owning foundational services across design, delivery, and post-launch performance develops strong instincts for multi-tenant reliability, API design, observability, and change management. The listing also points to practical exploration of AI tools and emerging frameworks, creating experience that translates across modern SaaS engineering orgs as teams standardize how AI is adopted safely and effectively.
This role suits senior engineers who prefer enabling other teams over shipping isolated features, and who enjoy multi-quarter technical bets with clear operational ownership. It will fit someone comfortable mentoring peers, navigating complex domains, and improving large Ruby/Rails and JavaScript/React systems through refactors, performance work, and well-documented platform interfaces.
The section above is editorial commentary from The SaaS Jobs, provided to help SaaS professionals understand the role in a broader industry context.
Job Description
About the Role:
We're looking for seasoned full-stack software engineers to join the teams behind Gusto's product platforms — the shared systems that our product teams build upon — to serve small business owners every day.
As a Staff Software Engineer, you'll operate across the full lifecycle of foundational systems: shaping architecture early in the design process, building self-service internal features and APIs, and owning their performance long after launch. That means engineering the core business engine, enabling product teams with reliable backend services, and setting the engineering standard for those around you.
If you're drawn to work that combines technical craft with real-world impact — helping power the livelihoods of millions using Gusto products — join us!
Here’s what you’ll do day-to-day:
- Design, build, and test Gusto core platform services – communications, reporting, dashboards, access, workflows, risk, payments, and compliance capabilities, among others
- Mentor other engineers to help solve some of the hardest technical problems out there in very complex domains and at a large scale
- Help scale one of the largest Ruby/Rails and Javascript/React applications in the world
- Collaborate with our Product Engineering, Product Management, Data, and Design teams to understand customer pain points, come up with solutions, and then prototype, iterate, and launch daily
Here’s what we're looking for:
- Successful applicants typically have 8+ years of software development experience
- Passion for creating scalable, efficient platforms for users
- Experience leveraging AI tools or systems to accelerate development, improve testing, and deliver new platform capabilities
- Curiosity and experimentation with emerging AI frameworks, applying and sharing best practices to evaluate and scale AI use safely across teams
- Experience owning multi-quarter projects that solve complex engineering problems and make measurable user impact at scale
- Experience with large scale refactors, performance and reliability issues, and a strong sense of ownership over all aspects of your platform area
- Ability to mentor engineers to maximize their performance and impact
Others:
- Experience in, or interest working in, Ruby on Rails
- Appreciation for a collaborative, test-driven environment
- Ability to build well-structured, maintainable, well-documented code
- Ability to effectively communicate across engineering teams and with business stakeholders
Do you prefer heavy feature development instead? Check out our Staff Software Engineer, Core Products job listing.
Our cash compensation amount for this role is targeted at $163,000–$204,000 in Denver & most remote locations, and $197,000–$247,000 for San Francisco & New York. Stock equity is additional. Final offer amounts are determined by multiple factors including candidate experience and expertise and may vary from the amounts listed above.
